It happened by itself - dreams were the main info dump format. And I followed up with many meditations looking for other options, history, more data.
It’s a long story how I finally came around to accepting this explanation.
I’ll post it with a collapsible so it’s it here but easy to scroll past as it’s not totally on topic, but it’s the story of how I realized this living past life connection.
Long Story
I knew this person, met him on a dating site, pretty much dismissed him as not compatible. He’s a fuckboi, he’s not even warm, he was flaky, bitchy, histrionic and unstable - not hot, mostly annoying - so I dropped it and went with other contacts. Done, no questions asked, him and hundreds like him, nothing special, I did not get a whiff of energetic importance.
Well, that was fine for a good year, then for no reason (on my side), out of left field, I remembered him and could not get him out of my head, and then the recurring dreams started, of him needing help. All metaphorical stuff but leaving this huge feeling of anxiety and needing to know he was ok and I had to do something. And me going “I so don’t care about that dude wtf is this!?”. That went on for about 3 months before I caved and texted him. And yup, he needed help.
Turned out, at the time I remembered him 3 months prior, he had called out to the universe for help… “ask and you shall receive” means sometimes other people get called in, and sometimes “other people”, is you. Why me? Why not a hundred other dating site randoms? Didn’t know. I chalked it up to a common contact in Azreal and thought I’d maybe been recruited to help as I was available to hear and respond. Ok, that’s easy. The whole world is magick; I live by that. I just asked back that it didn’t cost me this time. My assumption may have been incorrect - there’s that conscious mind insisting on having it’s reasons again. 
So there I am in contact, again, and he says he’s fine, fine, and slowly realizing he’s not. The help I am called to give starts playing out. And then the dreams hit again… now, about the past, of this 1940s dude, how he died and when I learned about that death, from the POV of his wife.
So she was me, and her hubby (who for reasons known only to my subconscious) he looked like Jeff Bridges
but I knew it was this dude. I recognized the energy signature of our spirits, albeit aggregate with different homo sapiens vessels.
Now, I tried to wiggle out of connecting this lady and me, mostly because this sucked and created a deeper relationship than I was up for. I don’t really “do” relationships, they’re always more drama and pain than they’re worth. Also seems a bit egotistical and I’m always saying dreams are mostly symbolic. But a) detailed death scenes about not-Jeff Bridges are a crappy metaphor for turning down a dating app contact, that’s just silly, and b) I just knew it in my bones, it’s like that sometimes.
It’s almost like, the old me was haunting the new me, like a ghost attachment can bring new addictions to you if the ghost is trying to get it’s fix by parasitizing a living human. I tried to banish it as a kind of intranquil spirit but that failed and didn’t really feel right - nobody cursed me, I couldn’t locate a spirit attachment - no random ghost of this woman still bent out of shape about hubby’s untimely death.
I did do my poppet spell, I have to update that spell again actually - this is the one “dissolve relationship working” that failed, and I know more about why now.
Thing is, you can’t really banish yourself. You can’t run away from yourself: you’re always right there. You can fragment and suppress parts of yourself, but actually resolving issues like that takes shadow work and integration, not rejection. Another way to consider it is as a “soul fragment” under shamanic principles - same idea though, needs integrating to deal with it.
… TL;DR, if you have tried everything to banish an idea, feeling or spirit haunting you, it might actually be a part of you you haven’t integrated yet, and that might be because it’s from a past life, so you experienced it through a different vessel, that was you and not you, and you didn’t integrate it fully the first time.
Some folks call this “karma” - a “karmic attachment” would be a valid label for this, I feel. I don’t usually use that word because it’s so badly misused, abusively so, elsewhere and I don’t want to be embroiled in that energy. But it is what it is, energy patterns exist and cause magnetic-like resonance and repulsion and attraction, affecting probabilities and sometime you can feel that very emotionally and viscerally.
What amazes me is a thought that, maybe, the reason I’m even here, when my last life was supposed to be my last life, (that was channeled by someone else but I agree) is because of my attachment from when I was “her”. Which means now I know the answer to “what the actual fuck am I even doing here!?”. “Karmic attachments” will do that to you, and I could not clear this one without doing this multi-life inner work.
Funny, because I bought into the “just declare all attachments null and void” a la Tom Montalk years ago, and it did feel better, but, I think, you actually have to know they exist to void them consciously. Karma is still optional, but you can’t fix an energy problem you don’t know you have.